int is_single(int re, int index, int* arr, int num) ; // 判断这个数是否出现一次。
void find_single(int* arr, int num,struct Single * ret);// 找到这个数

int is_single(int re, int index, int* arr, int num) 
{
	for (int i = 0; i < num; i++)
	{
		if (i == index)
			continue;
		if (arr[i] == re)
			return 0;
	}
	return 1;
}


struct is_single
{
    int x;
    int y;
};
void find_single(int* arr, int num,struct Single * ret)
{
	int index = 0;
	for (int i = 0; i < num; i++)
	{
		if (is_single(arr[i], i, arr, num))
			if(ret->x) ret->x= arr[i];
            else ret->y= arr[i];
	}
}

int main()
{
	int arr[] = { 1,1,6,2,3,4,4,3,5,2,8,8,11 };
	struct Single b = {0,0}
	int len = sizeof(arr) / sizeof(arr[0]);
	find_single(arr, len);
    printf("x=%d,y=%d\n",b.x,b.y);
	return 0;
}